Techniques for increasing interfacial stability

An enormous literature is devoted to surface pretreatments for durable bonding, as discussed in Chapter 3. Suffice it to say that chemical etching, surface conversion coatings, coupling agents and primers all have a place among the techniques. It would seem that 

The use of sealants to coat the edges of exposed joints has some merit in constituting a barrier to liquid water, but not water vapour. Most sealants are in fact more permeable than epoxy adhesives, so that a very thick layer would have to be applied in order to be effective. The usual joint-edge adhesive spew provides a useful barrier, as well as reducing stress concentrations. 

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